Mexicans.
Mexicans are the world's best hope of keeping Islam in check.
Promarily Catholic, they're the only culture having children at a rate close to the Muslims...
Islam spreading in southern Maya Mexico
CHIAPAS, MEXICO (Catholic Online) - Deep in southern Mexico, one does not expect to find Islam. Mexico is a very Catholic country although protestants, Jehovah Witnesses, and Mormons have made significant inroads there. Islam arrived in Chiapas brought by activist Europeans who came to rebuild the troubled communities.
The first arrivals came in 1996 just as the government started peace talks with the Zapatista rebels. Many locals were converted to evangelical Christianity, at the urging of missionaries from the U.S. and Europe, but Muslims quickly followed and spread a different message beside the Bible. Local converts explain that the Muslims and their families that settled in Chiapas have brought opportunities as well as faith to the people.
Among the opportunities are work--for a price. People who convert to Islam are frequently given jobs, which means a stable income. It is mostly Spanish-Muslims that have settled and established restaurants and carpentry shops, and are responsible for most of the conversions, although the sect's spiritual leader is reportedly a Muslim from Scotland.
In a popular move, the some of the Muslims have proceeded to align themselves with the Zapatistas, and echo their message of rebellion. With this, the Muslim outsiders quickly became insiders amongst the impoverished people. They have spread a message that is anti-capitalist, anti-government, and that people ought to return to the traditional life of Mohammed.
Islam spreading in southern Maya Mexico - International - Catholic Online